SickKids reports handful of 'rare' heart inflammation cases following COVID-19 vaccine

The Hospital for Sick Children (SickKids) is reporting a handful of cases of myocarditis — inflammation of the heart — after patients received the mRNA-based COVID-19 vaccines Pfizer or Moderna.

In a statement, a spokesperson for the hospital said it has seen approximately five such patients

"All of these patients responded well to treatment and the majority of patients with myocarditis following vaccination have not required admission," the statement from Jessamine Luck reads.

SickKids says the condition remains rare, and the vast majority of cases resolve on their own or are treated with an over-the-counter anti-inflammatory medication.

'Stressful and overwhelming'

Despite the rarity of the condition, some parents are feeling nervous about booking an appointment for their kids to get a second dose.

"I find it very stressful and overwhelming," said Christine Rose, a mother of two teenagers from Oshawa.

Rose says she wants to do the right thing for her kids, who have already received their first dose, but is weighing the risk of the virus against the potential risk of myocarditis.

"The kids want it, they want their life to go back to normal and see their friends," said Rose, adding she is pro-vaccine and will likely still go ahead with booking second doses.

Benefit of vaccine 'far outweighs the risk'

Ontario's incoming medical officer of health, Dr. Kieran Moore, urged parents not to worry at Thursday's COVID-19 briefing.

"It's very important that parents understand we have a very good safety system in Canada," Moore said, adding that the province is monitoring the situation very closely.

"At present we're not seeing any significant signal from the mRNA vaccines with the association of inflammation of the heart muscle or the sack that's around the heart, that's myocarditis or pericarditis, and we're learning from the American experience," Moore said, referring to a presentation Wednesday from a Centers for Disease Control and Prevention (CDC) advisory group.

Moore says the province is waiting for a review from the National Advisory Committee on Immunization (NACI) which should be released next week, and can make more additional information available to parents then.

"In our opinion ... the benefit of the vaccine far outweighs the risk of myocarditis or pericarditis at present," Moore said.

Dr. Jacob Udell, a cardiologist at Toronto General Hospital and Women's College Hospital, agrees.

He says he's fielding a lot of questions about the condition from patients, friends and family. He says while their concerns are valid, the risks are low.

"The message about this particular complication needs to be very clear, that the risk of 1 in 100,000 is several thousand times less than the risk of COVID infection itself," said Udell, adding that in the cases he's seen, symptoms have been mild and there was no permanent damage.

When it comes to what to look for, Udell says common symptoms of myocarditis include chest pain, shortness of breath, fatigue and fever.

PHAC: No clear association established

The Public Health Agency of Canada is also monitoring reports of heart inflammation following immunization.

The agency's latest weekly report on reported side effects following vaccination says that based on reports received, "Health Canada and PHAC are not seeing higher rates than would normally be expected in the general population."

"To date, no clear association has been established between myocarditis/pericarditis and mRNA vaccines, and to date, no regulatory action has been taken in Canada or internationally."